TOKYO (Reuters) - An earthquake with a preliminary magnitude of 6.2 jolted eastern Japan on Monday, public broadcaster NHK said, adding that no tsunami warning had been issued.

The quake also shook buildings in Tokyo, but there were no immediate reports of injuries or damage. Tokyo Electric Power Co said there were no reports of irregularities at its Fukushima Daiichi nuclear plant in north-eastern Japan or at its other nuclear facilities.

(Writing by Linda Sieg; Editing by Shinichi Saoshiro)